Seat structure for motor vehicle

ABSTRACT

A seat structure for a motor vehicle includes a front seat having a seat back capable of reclining backward, and a rear seat comprising a seat back capable of reclining forward and a seat cushion. In this seat structure, the seat cushion of the rear seat is pivotably supported at a front end, lower portion thereof by a vehicle body through a pivotal support member, such that the seat cushion is rotatable about an axis of the pivotal support member to be flipped over and stored above a floor panel in front of the rear seat. The seat back of the rear seat is pivotably supported at a lower portion by a vehicle body, and is able to recline forward after the seat cushion of the rear seat is rotated and stored, so as to be located in an original position of the seat cushion. When the seat back of the front seat is leaned backward, and the seat back of the rear seat is leaned forward to be in the original position of the seat cushion, the seat back of the front seat and the seat back of the rear seat cooperates with a load-carrying platform behind the rear seat to form a substantially continuous plane.

This application is a divisional of application Ser. No. 08/816,435,filed on Mar. 14, 1997, now U.S. Pat. No. 5,954,398 the entire contentsof which are hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to a seat structure for a motor vehicle,and in particular to such a seat structure wherein a seat or seats mayrecline forward or backward as needed to provide a flexible andeffective space in an interior compartment of the vehicle.

BACKGROUND OF THE INVENTION

Conventionally, when a motor vehicle is loaded with a large quantity ofloads or a load with a considerably large length, a seat back of itsrear seat is folded onto the upper face of a seat cushion of the rearseat, so as to expand a load-carrying platform or cargo deck. Further,Publication No. 46-4489 of examined Japanese Utility Model Applicationdiscloses a technique for further expanding the load-carrying platform,by rotating the seat cushion forward about a hinge provided at its frontend, lower portion to bring it into an upright position, and thenleaning the seat back forward so that the rear seat provides a flatplane that is substantially flush with the load-carrying platform behindthe rear seat.

In addition, Publication No. 2-5613 of examined Japanese PatentApplication discloses a double hinge structure including a linkmechanism in which one end of a link arm is connected to the front,lower portion of the seat cushion to be rotated, and the other end ofthe link arm is provided on a seat floor and pivotably supported by thefloor. With this double hinge mechanism, the seat may be selectivelyplaced in a seating position for normal use in which the seat cushion iskept in a substantially flat state, or a first folded position in whichthe seat back is rotated or leaned forward onto the upper face of theseat cushion and kept in the folded state, or a second folded positionin which the seat cushion is raised to the uprighrt position and theseat back is leaned forward into a space on the seat floor that isgenerated by raising the seat cushion.

The above-described conventional seat structure, which is proposed toflip the seat cushion forward into an upright position, cannot form aflat, extensive load-carrying floor that extends from the rear platformor cargo deck to an instrument panel in the front part of the vehicle,thus making it difficult to mount a load having a large length in thevehicle. Also, in the known seat structure, passengers cannot lay downcomfortably for a break.

In view of the above, it has been proposed to flip over the seat cushionof the rear seat and set it in position on a floor panel, and combiningthe rear seat with the front seat to form a more useful space in theinterior compartment of the vehicle.

If the known double hinge structure, which is rotatably supported abouttwo axes as described above, is applied for the above purpose, however,the seat cushion undergoes irregular movements when rotating about thedouble hinge structure, thus requiring careful operations where the seatcushion must be supported at its both sides. Thus, the operation to flipover the seat cushion becomes undesirably unsafe and complicated.Further, pivotal support portions of the double hinge structure may bedamaged due to distortion thereof in the lateral direction duringflipping-over of the seat cushion.

The rear seat may be divided into two sections in the ratio (6:4, forinstance) that makes the width of one section larger than that of theother section. In this case, the section having the smaller width may beflipped over without causing any problem, but the other section havingthe larger width cannot be successfully flipped over and set in positionsince it may interfere with a console box or the like that protrudestoward the rear seat in the middle of the interior compartment. In thiscase, too, the seat structure cannot fully meet the requirement to allowthe passengers to lay down on the seats.

SUMMARY OF THE INVENTION

The present invention has been developed in the light of theabove-described situations. It is therefore an object of the presentinvention to provide a seat structure for a motor vehicle, which may beeasily and safely altered as needed so that the entire front and rearseats can provide a space to allow a long load to be loaded onto thevehicle or allow passengers to lay down on the seats for a break.

The above object may be accomplished according to the principle of thepresent invention, which provides a seat structure for a motor vehicle,including a front seat having a seat back capable of reclining backward,and a rear seat comprising a seat back capable of reclining forward anda seat cushion, wherein the seat cushion of the rear seat is pivotablysupported at a front end, lower portion thereof by a vehicle bodythrough a pivotal support member, the seat cushion being rotatable aboutan axis of the pivotal support member to be flipped over and storedabove a floor panel in front of the rear seat; wherein said seat back ofthe rear seat is pivotably supported at a lower portion by a vehiclebody, and is cable of reclining forward after the seat cushion of therear seat is rotated and stored, so as to be located in an originalposition of the seat cushion; and wherein when the seat back of thefront seat is leaned backward, and the seat back of the rear seat isleaned forward to be in the original position of the seat cushion, theseat back of the front seat and the seat back of the rear seat cooperatewith a load-carrying platform behind the rear seat to form asubstantially continuous plane.

Thus, after the seat cushion of the rear seat is flipped over and storedabove the floor panel in front of the rear seat, the seat back is leanedforward into the original position of the seat cushion, and the seatback of the front seat is leaned backward, so that a substantiallycontinuous plane can be formed by the seat back of the front seat, seatback of the rear seat and the load-carrying platform or cargo deckbehind the rear seat. In this arrangement, a considerably long, usefulspace that extends from the instrument panel to the seat back of therear seat and further to the load-carrying platform may be obtained inthe interior compartment of the vehicle. Namely, the front and rearseats cooperate with the load-carrying platform to provide a full flat,reclining seat.

The space thus obtained permits a load having a large length, such as acarpet, a pair of skis, or a surfboard, to be easily accommodated in theinterior compartment of the vehicle, and also allows the passengers tocomfortably lay down on the seats.

After the seat cushion of the rear seat is flipped over and stored inthe space above the floor panel in front of the rear seat, only the seatback of the rear seat may be leaned forward to provide a cargo spacethat extends from the load-carrying platform to the back face of thefront seat.

After the seat cushion of the rear seat is brought up to the front seatand placed in the upright position, only the seat back of the rear seatmay be leaned forward to provide a cargo space that extends to the backface of the front seat.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1(A) and FIG. 1(B) are a perspective view and a schematic view,respectively, showing a seat arrangement in an interior compartment of amotor vehicle when the seat structure according to the present inventionis normally used;

FIG. 2 is a side view generally showing the interior construction of aseat cushion of a rear seat on the side of a passenger's seat, and alsoshowing a change in the posture of the seat cushion between the seatingposition and the reversed/stored position;

FIG. 3 is a perspective view showing a relationship between a flip-overdouble hinge mechanism of the seat cushion when placed in the seatingposition of FIG. 2, and its lock mechanism;

FIG. 4 is a perspective view showing a relationship between theflip-over double hinge mechanism of the seat cushion when placed in asubstantially upright position, and the lock mechanism;

FIG. 5 is a perspective view showing a relationship between theflip-over double hinge mechanism of the seat cushion when rotated abouta third hinge, and the lock mechanism that has been released;

FIG. 6 is a view showing rotating operations conducted to flip over theseat cushion of the rear seat on the side of the passenger's seat, alongwith trajectories obtained by the rotating operations;

FIG. 7(A) is a schematic view showing the layout of the seat structureof the invention obtained by flipping the rear seat forward into thesubstantially upright position;

FIG. 7(B) is a schematic view showing the layout of the seat structureof the invention obtained by flipping over the seat cushion of the rearseat and storing it above the floor panel in front of the rear seat, andleaning the seat back of the rear seat forward;

FIG. 7(C) is a schematic view showing the layout of the seat structureof the invention obtained by flipping over the seat cushion of the rearseat and storing it above the floor panel in front of the rear seat,leaning the seat back of the front seat backward, and leaning the seatback of the rear seat forward;

FIG. 8 is a schematic view showing the layout of the seat structure ofthe invention obtained by leaning the seat back of the front seatbackward;

FIG. 9 is a perspective view showing the seat arrangement in theinterior compartment where the front and rear seats on the side of thepassenger's seat are formed into a full flat reclining seat;

FIG. 10 is a side view of a seat cushion of a rear seat constructedaccording to a second embodiment of the present invention;

FIG. 11 is a view showing operations to rotate the rear seat and frontseat according to the second embodiment;

FIG. 12 is a side view showing a seat cushion of a rear seat behind thedriver's seat;

FIG. 13 is a perspective view showing a detachable mechanism for theseat cushion of the rear seat behind the driver's seat shown in FIG. 12;

FIG. 14 is a cross sectional view of the detachable mechanism takenalong V--V line in FIG. 13;

FIG. 15 is a front view of the detachable mechanism as seen in thedirection of arrow W in FIG. 13;

FIG. 16 is a perspective view showing the detachable mechanism when itis placed in its released or disengaged state;

FIG. 17 is a cross sectional view of the detachable mechanism whenplaced in the released position, taken along V'--V' line in FIG. 16;

FIG. 18 is a view showing operations to change the states of the rearseat and front seat on the side of the driver's seat; and

FIG. 19 is a perspective view showing the seat arrangement in theinterior compartment when the front and rear seats on the driver's sideand the front and rear seats on the passenger's side are arranged toprovide full flat reclining seats on the both sides.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the accompanying drawings, there will be described indetail presently preferred embodiments of the present invention. It is,however, to be understood that dimensions, shapes, relative positionsand other details of constituent components described in the preferredembodiments are merely mentioned for illustrative purposes only, andshould not be interpreted to limit the scope of the present inventionunless they are particularly specified in the description.

FIGS. 1(A) and 1(B) show the layout of a seat structure for a motorvehicle according to one embodiment of the present invention when seatsare in a normal seating condition. As shown in FIG. 1(B), the vehicleseat structure of the present embodiment consists of a front seat (1), arear seat (2), and a rear load-carrying platform or a cargo deck (3).The front seat (1) consists of a seat back 34 and a seat cushion 35.Actually, the front seat (1) includes a front passenger's seatconsisting of a seat back 34a and a seat cushion 35a, and a frontdriver's seat consisting of a seat back 34b and a seat cushion 35b, asshown in FIG. 1(A) These seat backs 34a, 34b can be reclined toward therear seat (2).

The rear seat (2) consists of a seat back 33 and a seat cushion 10constructed according to the present embodiment. This rear seat (2) isdivided into right and left sections (arranged in the width direction ofthe vehicle) in the ratio of 6:4, as shown in FIG. 1(A). Namely, in thepresent embodiment, the ratio of the first section of the rear seat (2)behind the front driver's seat (a larger section of the seat cushion) tothe second section thereof behind the front passenger's seat (a smallersection of the seat cushion) is 6:4. The first section of the rear seat(2) behind the front passenger's seat consists of a seat back 33a and aseat cushion 10a, and the second section behind the front driver's seatconsists of a seat back 33b and a seat cushion 10b. The postures ofthese right and left sections of the seat thus divided can be controlledindependently of each other. The seat back 33a and seat cushion 10a ofthe second section of the rear seat (2) behind the front passenger'sseat has substantially the same width as the seat back 34a and seatcushion 35a of the front seat (1).

The rear load-carrying platform (3) has a load-carrying floor or a deck30 which can carry a load D1 thereon, as shown in FIG. 1(B).

In the following, there will be described the construction of the seatback 33a and seat cushion 10a of the second section of the rear seatbehind the front passenger's seat.

Referring to FIG. 2, which shows a side view of the rear seat (2) behindthe front passenger's seat, the seat back 33a is pivotably supportedabout a rotary shaft 37 that connects a pair of brackets 36 fixed to araised face 31a of a floor (rear seat cushion floor) 31 of the rear seat(2), such that the seat back 33a can recline forward. The thickness ofthe seat back 33a and the shape of its back face are selected so thatthe seat back 33a, upon reclining forward as will be described later,cooperates with the load-carrying floor 30 to form a flat floor.

The seat cushion 10a incorporates a seat frame 10d that forms a frame ofthe sheet, as shown in FIG. 2. This seat frame 10d is provided with aflip-over double hinge mechanism (pivotal support member) 11 equippedwith a lock mechanism 20, as shown in FIGS. 2 and 3. This flip-overdouble hinge mechanism 11 is fixedly attached to a raised face 32a of afloor panel 32 in front of the rear sheet. Thus, the seat cushion 10a isconstructed such that the cushion 10a can flip over about the flip-overdouble hinge mechanism 11 toward the floor panel 32 in front of the rearsheet, as shown in the arrow G of FIG. 2.

More specifically described by referring to FIGS. 2 and 3, theabove-indicated double hinge mechanism 11 includes fixed brackets 12fixedly attached to the raised face 32a, hinge shafts (second hinge,fourth hinge) 15 supported along their axis by the fixed brackets 12,and substantially V-shaped hinge brackets (support member) 13 whoselower ends are rotatably supported by the hinge shafts 15. The doublehinge mechanism 11 further includes a support bracket 14 fixed to theupper ends of the hinge brackets 13, a hinge shaft (third hinge, fifthhinge) 16 supported at its axial ends by the bracket 14 so as to extendin parallel with the hinge shafts 15, and connecting bars 17 rotatablysupported by the hinge shaft 16. The connecting bars 17 are fixed to afront edge of the seat frame 10d.

The lock mechanism 20 includes a substantially U-shaped arm member 21fixed to the seat frame 10d, an engaging claw 24 adapted to engage withthe arm member 21 to lock the rotation of the frame 10d about the hingeshaft 16, and a retainer bracket 22 fixed to the hinge shaft 16. Theengaging claw 24 is rotatably supported by a rotary shaft 23 fitted inthe retainer bracket 22.

When the seat cushion 10a is placed on the floor 31 of the rear sheet(2) as shown in FIGS. 2 and 3, the engaging claw 24 is kept in aposition where its engaging groove 24a engages the arm member 21 unlessan external force is exerted on the engaging claw 24, whereby the lockedcondition is maintained. In this case, the seat frame 10d is not rotatedabout the hinge shaft 16, and is only rotatable about the hinge shafts15. On the other hand, if an external force is applied to the engagingclaw 24, for example, by pushing the rear end of the claw 24, theengagement between the engaging groove 24a and the arm member 21 isreleased, and the seat cushion 10a is allowed to rotate about the hingeshaft 16.

The engaging claw 24 may be provided with a bias means so that anelastic force biases the claw 24 in a locking direction in which theengaging groove 24a engages the arm member 21. In this case, the lockedcondition is released or eliminated and the seat, cushion 10a is allowedto rotate about the hinge shaft 16 when an external force is exerted onthe rear end of the engaging claw 24. When the engaging groove 24aengages the arm member 21 with no external force applied to the engagingclaw 24, on the other hand, the locked condition is favorably maintainedby the bias means, so that the seat frame 10d is favorably rotated aboutthe hinge shafts 15 without suffering from unsafety caused by anunexpected release of the locked condition during the rotation.

In the following, the operation of the thus constructed seat back 33aand seat cushion 10a will be explained referring to FIG. 2 through FIG.9.

FIG. 4 shows one operating state of the seat frame 10d where the seatcushion 10a is rotated 90° about the hinge shaft 15 to stand uprightwhile the engaging claw 24 is being placed in the locking position.Thus, the seat cushion 10a is initially rotated about the hinge shafts15 until it reaches a substantially upright position, while the lockedcondition of the hinge shaft 16 is being maintained.

The seat cushion 10a is rotated about the hinge shafts 15 with a largerradius than that of rotation about the hinge shaft 16, and the axis ofthe hinge shafts 15 is located lower (closer to the floor panel) andcloser to the front seat (1) than the axis of the hinge shaft 16. Thus,the seat cushion 10a is arcuately rotated along a trajectory A, as shownin FIG. 6, such that it becomes closer to the front seat (1) and also tothe floor panel 32. In this condition, the hinge shaft 16 is alsorotated about the hinge shaft 15 (from the position L to the position Hin FIG. 6) along with the hinge brackets 13 and support bracket 14, tomove toward the front seat (1) and the floor panel 32 (first operatingstep P1). Although a relatively large force is required in this firstoperating step P1 due to the rotation of the above members 16, 13, 14,the seat cushion 10a can be stably rotated only about the hinge shafts15, rather than about two rotary axes of the hinge shafts 15 and hingeshaft 16, thus eliminating a complicated operation and assuring improvedsafety. In this arrangement, the flip-over double hinge mechanism 11makes a smooth movement and is thus protected against damages.

The lock mechanism 20 is released when the seat cushion 10a reaches thesubstantially upright position. As shown in FIG. 5 showing the state ofthe seat frame 10d when the lock mechanism 20 is placed in the releasedposition, the engaging groove 24a of the engaging claw 24 is disengagedfrom the arm member 21 by pushing the rear end of the engaging claw 24,for example, so that the locked condition is eliminated. As a result,the seat frame 10d, i.e., seat cushion 10a, is allowed to rotate aboutthe hinge shaft 16 and fold down toward the floor panel 32 in front ofthe rear seat. At this time, the seat cushion 35a and seat back 34a ofthe front seat (1) are placed in the forefront positions.

Since the radius of rotation of the seat cushion 10a about the hingeshaft 16 is smaller than that of rotation about the hinge shafts 15, theseat cushion 10a is arcuately rotated about the hinge shaft 16 along atrajectory B without interfering with the back face 45 of the frontseat, until the cushion 10 reaches a substantially horizontal positionand is laid down above the floor panel 32 (second operating step P2).

After avoiding the interference with the back face 45 of the front seatas described above, the seat cushion 10a is further rotated about thehinge shafts 15. With this rotation, the hinge shaft 16 is finallyplaced in the position M shown in FIG. 6.

With the axis of the hinge shafts 15 being located closer to the frontseat and lower (closer to the floor panel) than the axis of the hingeshaft 16 as described above, the seat cushion 10a is arcuately rotatedalong a trajectory C until it falls exactly down to the position of thefloor panel 32, as shown in FIG. 6. Thus, the seat cushion 10a favorablyfits in a space 32c above the floor panel 32, and can be thus placed ina reversed/stored position 10a' (third operating step P3).

In the present embodiment as described above, the seat cushion 10a ofthe rear seat (2) can be easily and safely flipped over to fit in thespace, without interfering with the front seat (a). As shown in FIG.7(A), the seat cushion 10a of the rear seat (2) may be flipped forwardto the substantially upright position 10a" only with the operation ofthe first operating step P1. Then, the seat back 33a may be leanedforward to the position where the seat cushion 10a was originallylocated (original position), to be placed in a lean-forward position33a' as shown in FIG. 6, so that a flat back face of the seat back 33aprovides a load-carrying floor 30a. Thus, the rear seat (2) can be usedas a part of the load-carrying platform that also includes theload-carrying floor 30, thereby enabling a load D2 having a greaterlength than the above-indicated load D1 to be mounted on theload-carrying platform 30, 30a within the interior compartment.

By carrying out the first through third operating steps P1-P3, the seatcushion 10a of the rear seat (a) may be rotated and flipped over to beplaced in the reversed/stored position 10', as shown in FIG. 7(B).Subsequently, the seat back 33a may be leaned forward to be placed inthe lean-forward position 33a' so that the load-carrying floor 30 cancarry thereon a load D3 having a greater length than the load D2.

In addition, the seat cushion 10a of the rear seat (2) mass be rotatedand flipped over to be placed in the reversed/stored position 10', andthe seat back 34a of the front seat (1) may be leaned backward byreleasing a lock mechanism (not shown), to placed in a lean-backwardposition 34a', as shown in FIG. 7(C). The seat back 33a of the rear seat(2) is then leaned forward to be placed in the lean-forward position33a'. Thus, the front seat (1) and the rear seat (2) may be altered toprovide a fully flat reclining seat as shown in FIG. 9, so that aconsiderably long load D4, such as a carpet, a pair of skies or asurfboard, which extends up to an instrumental panel 70 can be mountedwithin the vehicle compartment.

As shown in FIG. 8 only the seat back 34a of the front seat (2) may beleaned backward to be placed in the lean-backward position 34a', toprovide a front-seat full flat state used when a passenger takes a breakfor a while.

The above-described operating steps may be carried out in the reverseorder so as to return the seat cushion 10a from the reversed/storedposition 10a' to the seating position.

FIGS. 10 and 11 show the construction of a seat structure for a motorvehicle according to a second embodiment of the present invention, inwhich a single hinge mechanism is employed in a seat cushion 10a behinda passenger's seat. Referring to these figures, the second embodimentrelated to the seat cushion 10a behind the passenger's seat will beexplained.

The second embodiment is constructed without using two hinges (doublehinge mechanism) as used in the previous embodiment, to provide a fullflat reclining seat as shown in FIG. 7(C) and FIG. 9 by means of thesingle hinge mechanism.

Referring first to FIG. 10, a pair of single hinge devices (pivotalsupport members) 50 are provided instead of the above-describedflip-over double hinge mechanism 11, in the front-end, lower portion ofthe seat cushion 10a of the rear seat (2). Each single hinge device 50mainly consists of a fixed bracket (first bracket member) 51, a hingeshaft (first hinge) 52 fittedly inserted through the fixed bracket 51,and a hinge bracket (second bracket member) 53 that is rotatable aboutthe hinge shaft 52. The fixed bracket 52 is secured to a front endportion 31b of a floor 31 of the rear seat (2) with a plurality of bolts58, and the hinge bracket 53 is fixed to the seat frame 10d of the seatcushion 10a with a plurality of bolts 59. In this arrangement, the seatcushion 10 is rotatable about the hinge shaft 52.

More specifically, the fixed bracket 51 is attached to the front endportion 31b such that the axis of the hinge shaft 52 inserted throughthe bracket 51, i.e., the center of rotation of the seat cushion 10a, islocated at a fixed height Y as measured from the front end face 31b ofthe floor 31, and protrudes forward by a fixed distance Z as measuredfrom a raised face 32a on the rear side of the floor panel 32. Namely,the axis of the hinge shaft 52 is located forwardly and upwardly of thefront end face 31.

The above-indicated height Y and protruding distance Z are determined sothat when the seat cushion 10a of the rear seat (2) is placed in thereversed/stored position 10a' and the front seat (1) and rear seat (2)are set in the form of a full flat reclining seat, the seat cushion 10ais accommodated in the space 32c above the floor panel 32 in thefollowing manner (refer to FIG. 11).

Namely, the above dimensions Y, Z are determined so that the seatcushion 10a is completely or fully fitted in the space 32 such that thefront end face 10g of the seat cushion 10a abuts on the raised face 32a,and the back face of the seat cushion 10a is made substantiallyhorizontal, preferably with a small clearance between the upper face 10c(in the original position) and the floor panel 32. In this arrangement,the single hinge devices 50 do not protrude from the seat cushion 10a,and are prevented from interfering with the passenger.

Reference numeral 60 in FIG. 10 denotes an engaging member mounted onthe floor 31 located below the rear portion of the seat cushion 10a. Theseat cushion 10a, when normally used, is retained such that its rear endportion is held onto the floor 31 by means of an engagement between theseat frame 10d and the engaging member 60. If the engagement with theengaging member 60 is released, on the other hand, the seat cushion 10abecomes rotatable about the hinge shafts 52.

In FIG. 10, reference numeral 54 denotes a pair of brackets, thatsupport the seat back 33a like the above-indicated brackets 36, and thebrackets 54 are secured to the floor 31 with bolts 56. As shown in FIG.10, a rotary shaft 55 extends between the pair of brackets 54 to passthrough the lower portion of the seat back 33a. Accordingly, the seatback 33a is pivotably supported by the rotary shaft 55 and can be leanedforward about the rotary shaft; 55.

In the following, the operation of the seat cushion 10a of the thusconstructed second embodiment will be described referring to FIG. 11.Two-dot chain lines in FIG. 11 indicate the seat cushion 10a when it isnormally used, and solid lines indicate the cushion 10a when it isplaced in the full flat reclining state.

Initially, the engaging member 60 shown in FIG. 10 is disengaged orreleased from the seat frame 10d, and the seat cushion 10a is rotatedabout 180° about the hinge shafts 52 as indicated by the arrow x in FIG.11, so as to be set above the floor panel 32.

As described above, the axis of the hinge shafts 52 is located ahead ofthe raised face 32a of the floor panel 32 by the protruding distance Z,and above the front end face 31b of the floor 31 by the height Y.Accordingly, the seat cushion 10a, when rotated about 180° about thehinge shafts 52, completely fits in the space 32c above the floor panel32 behind the front seat (1).

Since the front portion of the seat cushion 10a normally has arelatively large thickness, the front end 10g of the upper face of theseat cushion 10a that is spaced apart from the hinge shafts 52 abuts onthe raised face 32a when the seat cushion 10a is rotated about the hingeshafts 52 and accommodated in the space 32c above the floor panel 32.Thus, the seat cushion 10a is stably supported by two points, i.e., atthe hinge shafts 52 and the front end 10g of the upper face, and is thuskept in a substantially horizontal state while being loosely held in theair within the space 32c such that the seating surface (in the originalposition) 10c does not directly contact the floor panel 32. In thesecond embodiment, therefore, the seating surface of the cushion isadvantageously prevented from being contaminated even in such asituation that the floor panel 32 gets wet on rainy days or the like.

Subsequently, the seat back 34a of the front seat (1) is rotated aboutthe hinge shaft 57 and leaned backward as indicated by the arrow y inFIG. 11 by releasing a lock mechanism (not shown), to rest on the backface of the seat cushion 10a that is placed in the reversed/storedposition 10a'. Thus, the seat back 34a is brought into the position asdenoted by 34a' in FIG. 11.

Further, the seat back 33a of the rear seat is rotated about the hingeshaft 55 and leaned forward as indicated by the arrow z in FIG. 11 byreleasing a lock mechanism (not shown), to be set on the floor 31 andplaced in the position as denoted by 33a' in FIG. 11.

In this manner, the seat cushion 35a and seat back 34a' of the frontseat (1) and the back face of the seat back 33a' of the rear seat (2)cooperate to form a single flat plane as indicated by solid lines inFIG. 11, with the seat cushion 10a being accommodated in the space 32aabove the floor panel 32, thereby to provide a full flat reclining seatsimilar to that shown in FIG. 9.

Thus, in the second embodiment, the seat cushion 10a is brought into thereversed/stored position 10a' in a single rotating operation by use ofthe single hinge devices 50 having a simple structure, rather than theflip-over double hinge mechanism 11 of the first embodiment having acomplicated structure, so as to establish the form of the full flatreclining seat as shown in FIG. 9. This enables a considerably long,flat space to be further easily and smoothly formed in the interiorcompartment, which space extends from the instrument panel 70 to therear end of the load-carrying floor 30.

There will be next explained the construction of a seat back 33b and aseat cushion 10b that accounts for 60% of the entire rear seat (2) andis located behind the front driver's seat.

Referring to FIG. 12, which shows a side view of the rear seat (2)facing the back face of the front driver's seat, the seat back 33b ispivotably supported about a rotary shaft 55 disposed between a pair ofbrackets 54 fixed to the floor 31 of the rear seat (2), like the seatback 33a of the second embodiment facing the back surface of the frontpassenger's seat. The thickness of the seat back 33b and the shape ofits back face are determined so that the seat back 33b, when leanedforward, cooperates with the load-carrying floor 30 to provide asubstantially flat floor. An engaging member 60 as described above isprovided on the floor 31.

The seat cushion 10b incorporates a seat frame 10f that forms the frameof the seat, as shown in FIG. 12. At the front end portion of the seatframe 10f, there is provided a detachable mechanism (detachableconnecting member) 80 which rotatably connects the seat frame 10f withthe floor 31 under the rear seat (2), and is also capable of separatingthe frame 10f and the floor 31 from each other. This detachablemechanism 80 will be hereinafter described in detail.

The detachable mechanism 80 has a fixed portion 82 on the side of thefloor 31, and an engaging portion 90 on the side of the seat frame 10f.FIG. 13 is a perspective view of the detachable mechanism 80 in whichthe seat frame 10f is rotated until the frame 10f becomes substantiallyvertical with respect to the floor 31. FIG. 14 is a cross sectional viewof the detachable mechanism 80 taken along V--V line in FIG. 13, andFIG. 15 is a front view as seen in the direction of arrow W in FIG. 13.The detachable mechanism 80 in this operating state will be describedreferring to FIG. 13 through FIG. 15.

Initially, the fixed portion 82 on the side of the floor 31 consists ofa fixed bracket 84 connected integrally to a pair of L-shaped brackets86 that are spaced apart from each other, and hinge shafts 88 attachedto the respective brackets 86.

More specifically, a pair of side walls 87 are formed along oppositevertical portions of each of the brackets 86, and the hinge shaft 88extends between distal end portions of these side walls 87. The fixedbracket 84 is fixed by a plurality of bolts 85 to the front end portion31b of the floor 31 of the rear seat (2) at horizontal portions of theL-shaped brackets 86 where these brackets 84, 86 are connected to eachother.

On the other hand, the engaging portion 90 on the side of the seat frame10f mainly includes a main plate 92 formed in U shape and fixed at itsback face to the seat frame 10f, and a pair of coaxial rotary shafts 96respectively mounted on a pair of vertical portions of the main plate92, namely, a pair of side plate portions 94. The engaging portion 90further includes a pair of arms 98 that are rotatable about therespective rotary shafts 96, a pair of engaging claws 100 that rotateabout the rotary shafts 96 along with the arms 98, and a handle 102having opposite ends connected to the respective arms 98 for connectingthe pair of arms 98 with each other.

More specifically, as shown in FIG. 14, an engaging groove 94a is formedin one corner of the distal end of each side plate portion 94, to extendtoward the corresponding rotary shaft 96, so that each of the hingeshafts 88 can fit in or engage the engaging groove 94a. Each of theengaging claws 100 is formed with an engaging groove 100a similar to theabove engaging groove 94a, such that these grooves 94a, 100a areperpendicular to each other. This engaging groove 100a is alsoengageable with the corresponding hinge shaft 88. Namely, where thehinge shafts 88 engage the engaging grooves 94a, the hinge shafts 88 arealso engageable with the engaging grooves 100a at the same time. In theoperating state as shown in FIG. 13 through FIG. 15, therefore, thehinge shafts 88 are retained in the engaging grooves 94a and engaginggrooves 100a, and thus the engaging portion 90 of the detachablemechanism 80 is rotatable about the hinge shafts 88. Accordingly, thedetachable mechanism 80 in this state serves as a hinge, which enablesthe seat frame 10f, namely, the seat cushion 10b, to be freely rotatedabout the hinge shafts 88 of the fixed portion 82.

A stopper pin 110 is mounted on the distal end portion of each of thearms 98, to extend toward the corresponding side plate portion 94, whilea guide aperture 112 is formed through each of the side plates 94. Thestopper pin 110 is inserted through this guide aperture 112 such thatthe pin 110 can freely slide within the aperture 112. Namely, althoughthe arm 98 is rotatable about the rotary shaft 96, the range of therotation of the arm 98 is actually limited to the range of the movementof the stopper pin 110 within the guide aperture 112.

Reference numeral 115 denotes a lock pin that passes through thecorresponding arm 98 and engaging claw 110, and permits the engagingclaw 110 to be rotated together with the arm 98 about the rotary shaft96.

Further, a sleeve 104 is fitted on each of the rotary shafts 96 toextend around the shaft 96, and a coil spring 106 is fitted on thesleeve 104. One end of this coil spring 106 is received in a notch 108formed in the side plate portion 94, and the other end of the spring 106is received in a notch 99 formed in the arm 98. In this arrangement, thearm 98 is always biased by the coil spring 106 within the movable rangeof the stopper pin 110, so that the engaging claw 100 engages thecorresponding hinge shaft 88.

Reference numeral 114 in FIG. 14 denotes a bracket fixed to the seatframe 10f. The main plate 92 is coupled to this bracket 114 with aplurality of bolts 116, to be connected to the seat frame 10f.

Referring to FIG. 12 and FIGS. 16-19, the operation of the seat cushion10b thus constructed will be explained. FIG. 16 is a perspective view ofthe detachable mechanism 80 in a detached state, and FIG. 17 is a crosssectional view of the detachable mechanism 80 in the detached state,taken along V'--V' line in FIG. 18.

Initially, the engaging member 60 is disengaged from the seat frame 10fof the seat cushion 10b that is in the state of FIG. 12, and the seatcushion 10b is rotated about 90° along the arrow x' about the hingeshafts 88 as shown in FIG. 18, so that the cushion 10b stands up and isplaced in the upright position 10b".

In this condition, the handle 102 is then operated in the direction asindicated by the arrow S in FIGS. 16 and 17, so as to rotate the arms 98about the rotary shafts 96 against the bias force of the coil springs106.

As a result, the pair of engaging claws 100 connected by the lock pins114 to the arms 98 are rotated about the rotary shafts 96 as shown inthe arrow T in FIG. 17 so that the engagement between the hinge shafts88 and the engaging grooves 100a is released. Thus, the hinge shafts 88are detached from the engaging grooves 94a of the side plate portions94.

In this condition, therefore, the engaging portion 90 is separated fromthe fixed portion 82 along the engaging grooves 94a, by holding andoperating the handle 102 in the direction as indicated by the arrow U inFIGS. 16 and 17. Thus, the seat frame 10f, namely, the seat cushion 10b,is separated or removed from the floor 31, as indicated by the arrow U'in FIG. 18.

Subsequently, the seat back 34b of the front seat (1) is rotated aboutthe hinge shaft 57 and leaned backward as indicated by the arrow y' inFIG. 18, after releasing a lock mechanism (not shown), so that the seatback 34b is brought into the position 34b' as shown in FIG. 18.

Then, the seat back 33b is rotated about the hinge shaft 55 and leanedforward as indicated by the arrow z' in FIG. 18, after releasing a lockmechanism (not shown), so that the seat cushion 10b is set on the floor31 from which the seat cushion 10b is removed. Thus, the seat back 33bis placed in the position (state) 33b' as shown in FIG. 18.

As a result, the seat cushion 35b and seat back 34b' of the front seat(1) and the seat back 33b' of the rear seat (2) form a single flat planeas indicated by solid lines in FIG. 18, to thus provide a full flatreclining seat on the side of the front driver's seat as well as on thefront passenger's seat, as shown in FIG. 19.

In this connection, the seat cushion 10b having a large dimension in thewidth direction of the vehicle, specifically, 60% of the entire width ofthe rear seat, reaches a substantially middle part of the interiorcompartment. Where a console box 120 or the like on the floor of thesubstantially middle part of the interior compartment protrudes towardthe rear seat (2) as shown in FIG. 18, for example, the seat cushion 10bcannot be normally flipped over and stored just above the floor panel 32like the seat cushion 10a on the side of the front passenger's seat,because of the console box 230 or the like that interferes with thecushion 10b. In the present embodiment, the seat cushion 10b is removedin the manner as described above, to easily produce the fully flatreclining seat.

This arrangement enables the driver to lay down while the vehicle isstopped, for example. FIG. 19 shows full flat reclining seats providedon both sides of the front driver's seat and the front passenger's seat.With the seats reclining in this way, at least two people can lay downwhile the vehicle is stopped, thus permitting the use of the vehicle asa camping car. Depending upon situations, the seats on the side of thefront passenger's seat may be kept in the normal, seating positions, andonly the seats on the side of the front driver's seat may be leaned toprovide a full-flat reclining seat. Further, the seat cushion 10b andseat back 33b behind the front driver's seat may be placed in thepositions as shown in FIGS. 7(A) and 7(B), so that a load having alarger width than the loads D2, D3 can be mounted on the vehicle.

The detachable mechanism 80 consists of a simple latch structure, andcan be thus used as a hinge with high reliability, while making itconsiderably easy to attach and detach the seat cushion 10b to and fromthe floor 31.

To return the seat cushion 10b to the seating position, theabove-described operations can be carried out in the reverse order.

In the seat structure of the present invention as explained above, wherethe rear seat (2) is a split-type seat consisting of a first section onthe side of the front driver's seat which accounts for 60% of the entirerear seat, and a second section on the side of the front passenger'sseat which accounts for 40% of the entire rear seat and whose width issubstantially equal to that of the front seat (1), for example, the seatcushion 10a on the side of the front passenger's seat is flipped overand accommodated in the space 32c just above the floor panel 32, so asto easily provide a full flat reclining seat consisting of the eatcushion 35a, seat back 34a' and seat back 33a'. On the other and, theseat cushion 10b on the side of the front driver's seat, which reaches asubstantially middle part of the interior compartment, cannot be flippedover and accommodated in the space 32c just above the floor panel 32, inthe presence of the console box 120 or the like located in the middlepart of the interior compartment. If the seat cushion 10b is madedetachable as described above, a full flat reclining seat consisting ofthe seat cushion 35b, seat back 34b' and seat back 33b' can be similarlyeasily formed by removing the seat cushion 10b. Thus, the seat structureof the motor vehicle may be used in various ways depending upon the useof the seats, even if the seat structure includes the rear seat (2) thatis divided into two sections in the ratio of 6:4.

While the rear seat (2) is split in the width direction of the vehicleinto two sections in the ratio of 6:4 in the illustrated embodiments,the rear seat (2) is not limited to this type, but may be constructedsuch that the seat cushion and seat back are divided into three sectionsin the ratio of 4:2:4. Namely, the seat cushion and seat back facing theback face of the front passenger's seat accounts for 40% of the entirerear seat, and the seat cushion and seat back facing the back face ofthe front driver's seat also accounts for 40% of the entire rear seat,so that both of these seat cushions may be flipped over and accommodatedin the space 32c just above the floor panel 32. In this case, only themiddle portion (accounting for 20% of the entire rear seat) of the rearseat may be made detachable or removable as described above, since thisportion might interfere with the console box 120 or the like if it isflipped over. If the middle portion does not interfere with anything,this portion need not be removed.

What is claimed is:
 1. A seat structure for a motor vehicle comprising:arear seat having,a rear seat cushion pivotably supported by a vehiclebody through a pivotal support member provided in a front end portionthereof, said rear seat cushion being rotatable about the pivotalsupport member between a first position in which said rear seat cushionis placed on a rear seat cushion floor, and a second position in whichsaid rear seat cushion is placed above a floor panel in front of therear seat to form a first surface, and a rear seat back, at least a partof which reclines forward to form a second surface, said first surfacebeing substantially lower than the second surface, when said rear seatcushion is in said second position; and a front seat having a front seatback that reclines rearward to form a third surface above said firstsurface, the third surface being substantially level and continuous withthe second surface, wherein said pivotal support member has a doublehinge structure including a first hinge provided on a raised portionthat extends from the floor panel in front of the rear seat to the rearseat cushion floor that normally bears said rear seat cushion, and asecond hinge provided in said front end portion of the rear seatcushion, said first hinge is directly supported by said raised face,while said second hinge being supported by a support member rotatableabout said first hinge such that a radius of rotation about said secondhinge is smaller than a radius of rotation about said first hinge, and alock mechanism is provided between said support member and said secondhinge for selectively restricting rotation of said rear seat cushionabout said second hinge, wherein said rear seat cushion rotates aboutsaid first hinge between said first position and a third position,located between said first and second positions, while said lockmechanism restricts rotation about said second hinge, rotates about saidsecond hinge between said third position and a fourth position, locatedbetween said third and second positions, and rotates about said firsthinge between said fourth and second positions.
 2. A seat structure fora motor vehicle according to claim 1, wherein each of said rear seatcushion and said rear seat back of the rear seat are divided in a widthdirection of the vehicle into at least two portions arranged in parallelwith each other, and whereina part of the divided rear seat cushion isrotatably supported at a front end portion thereof by the vehicle bodythrough said pivotal support member, and a remaining part of the rearseat cushion is supported by the vehicle body through a detachableconnecting member provided in a front end portion of the rear seatcushion.
 3. A seat structure for a motor vehicle according to claim 1,wherein said seat cushion and said seat back of the rear seat is dividedin a width direction of the vehicle into at least two sections that arearranged in parallel with each other, a part of the divided seat cushionbeing rotatable independently to be flipped over and stored above saidfloor panel in front of the rear seat, a part of said seat backcorresponding to said part of the seat cushion being capable ofreclining forward independently.
 4. A seat structure for a motor vehicleaccording to claim 1, wherein said third position is where said rearseat cushion is substantially vertical.
 5. A seat structure for a motorvehicle according to claim 1, wherein said fourth position is where saidrear seat cushion is substantially horizontal.